appearance, so that only two divisions can be made with any certainty
at all. These are dependent upon a secondary characteristic, viz, the
presence of epidote in large or small quantities. The epidote occurs
in the form of lenses arranged parallel to the planes of schistosity,
reaching as high as five feet in thickness and grading from that down
to the size of minute grains. Accompanying this lenticular epidote is
a large development of quartz in lenses, which, however, do not attain
quite such a size as those of epidote. Both the quartz and epidote are
practically insoluble and lie scattered over the surface in blocks of
all sizes. In places they form an almost complete carpet and protect
the surface from removal. The resulting soil, where not too heavily
encumbered with the epidote blocks, is rich and well adapted to
farming, on account of the potash and calcium contained in the epidote
and feldspar.

Except along the narrow canyons in the Tertiary baselevel the rock is
rarely seen unless badly weathered. The light bluish green color of
the fresh rock changes on exposure to a dull gray or yellow, and the
massive ledges and slabs split up into thin schistose layers. It is
quite compact in appearance, and as a rule very few macroscopic
crystals can be seen in it.

A general separation can be made into an epidotic division
characterized by an abundance of macroscopic epidote and a
non-epidotic division with microscopic epidote. These divisions are
accented by the general finer texture of the epidotic schist.

The schists can be definitely called volcanic in many cases, from
macroscopic characters, such as the component minerals and basaltic
arrangement. In most cases, the services of the microscope are